In the mid-1980s, Havel Brothers (Indianapolis) installed an Andover Controls (Andover, MD) AC256 building automation system in Cummins’ general office building and parts distribution center in Columbus, Indiana.
Cummins’ facility staff were extremely happy with the system’s performance, so when a new control system for the company’s fuel system plant (FSP) came up for bid in the early 90s, the facility’s staff voiced a strong preference to stay with the Andover Controls product line and Havel Brothers. As a result, Cummins selected what was then Andover’s next generation product, Infinity, for installation in the FSP. Cummins, Havel Brothers, and Gary Kuzma of the A/E firm Jeumeuth, Obata & Kassabaum, Inc. (JOK, Houston) worked together to design and lay out the system, which utilizes the FSP’s existing Ethernet TCP/IP network.
Precise Environmental ControlThe environment in Cummins’ FSP must be precisely controlled. The entire 480,000-sq-ft facility is air conditioned year-round, and the temperature in the general spaces must be constantly maintained at 72˚F (+ 1.5˚ to ensure a maximum five-micron tolerance on all fuel systems measurements. Even closer tolerances must be adhered to in the labs. For example, in the FSP’s state-of-the-art Dimensional Metrology Center, measurements are done to a maximum one-micron tolerance and the temperature must be maintained at a constant 68˚F (+.5˚) to allow for only the most minute expansion or contraction of fuel system components. Although controlling this environment may appear complicated on the surface, the facilities staff finds the system very user-friendly. Features such as HOA switches on the Infinity SCX 920 controllers make troubleshooting easy, and Infinity DCX 250 touch screen displays mounted in every air handler room provide maintenance personnel and plant engineers access to all points on all AHUs from anywhere in the facility.
Beyond HvacThe installation manages more than hvac at Cummins by controlling and monitoring the facility’s wastewater treatment system. Previously, Cummins paid $.44/gal to have an outside company treat its wastewater. Now with its own in-house system, Infinity monitors tank levels, views differential pressures, and enables pumps, valves, solenoids, and more. By treating its own wastewater, Cummins now spends only $.25/gal and anticipates a 13-month payback on its $100,000 initial investment.
Infinity also controls and monitors a Reverse Osmosis (RO) system and a chemical treatment system. Both are important in treating the chilled water and conditioned water used in equipment cooling and the parts wash systems. Infinity also monitors city water pressure, tank levels, differential pressure, to name a few, and also controls biocide and acid injection to maintain the correct pH and conductivity. And with Infinity, the manufacturing lines can monitor their total water consumption and track the cost of their utilities using Infinity’s reporting capabilities.
Blending InInfinity integrates to Cummins’ Rapier Computerized Maintenance Management System (CMMS) via the SX 8000 front-end workstation and an Andover Controls Plain English® driver. The Rapier system keeps track of all equipment assets such as service history. The SX workstation forwards designated equipment alarms to the Rapier system, which in turn, creates applicable workorders and pages the appropriate trade personnel to handle the problem.
According to Frank Clark, director of plant engineering at FSP, Infinity’s ability to provide this “non-traditional” hvac control was a major selling factor for Cummins. “There is so much versatility to this product,” said Clark. “In addition to the standard controlling and/or monitoring of our chillers, boilers, AHUs, RTUs, cooling towers, VAV boxes, and boilers, we are using Infinity to do so much more, such as wastewater, chemical, and RO treatment systems. Because our systems are so unique here, we needed a versatile control system to manage them.”
Future PlansChris Smith, project sales engineer at Havel Brothers, said that Cummins has several new control projects scheduled for the near future. Plans call for the system to control and monitor additional AHUs; load demand on three new air compressors (1-400 HP and 2-250HP Ingersoll Rand), operating them at optimal efficiency; and lighting, boilers, and numerous gauge labs.
Plans also call for Infinity to provide air curtain control in the shipping and receiving areas. It will control the flow of a powerful wall of air that will prevent the infiltration of unconditioned outside air into the building when the large overhead doors are open for pickups and deliveries. In order to aid Cummins in its Demand Side Management Program of electrical energy, Havel Brothers and Infinity will also be providing a lighting control system with an estimated savings of $60,000 per year. ES